1. Field of the Invention
The present invention relates to a disk drive equipped with a mechanism for preventing rattling of a traverse unit produced either by vibrations of a motor for rotationally driving a turntable or by unintentional movement caused by eccentricity of a disk.
2. Related Art
FIGS. 8A and 8B show a conventional disk drive equipped with a tray. A disk placed on the tray 1 is moved into a playback position as the disk is transported in, where a traverse unit 2 is elevated, and thus the disk is placed on a turntable 3 and damped. Conversely, when the disk should be taken out after playback, the traverse unit 2 is lowered to thereby move the disk placed on the turntable 3 onto the tray 1 and then the disk is carried out together with the tray.
When the tray 1 has been carried out, the traverse unit 2 has descended obliquely as shown in FIG. 8A. Accordingly, if a disk is placed on the tray 1 and carried into the disk drive, the traverse unit 2 ascends and the disk is placed on the turntable 3. Furthermore, the disk is squeezed within a damper 4 and clamped.
A protrusion 5 is formed in the center of the front side of a traverse holder 7 combined with the traverse unit 2 on the front-end side. The protrusion 5 is fitted in a cam groove formed in a rack-loading unit 6. When the rack loading unit 6 slides in the left and right direction, the front ends of the traverse holder 7 and traverse unit 2 ascend and descend about their rear ends.
The traverse unit 2 is mounted to a chassis 8 in this way and moves up and down about its rear end. The turntable 3, an optical pickup, and other components are mounted to the traverse unit 2. The traverse unit 2 is then mounted to the chassis 8. That is, the traverse unit 2 is tilted and inserted into the space formed in the chassis 8 to be stably supported to the chassis 8 by a holding mechanism. Furthermore, the traverse unit 2 is formed fundamentally free of rattling by the holding mechanism.
However, the turntable 3 is mounted to the traverse unit 2 and the disk fitted to the turntable 3 is rotationally driven at high speed by the motor. At this time, if the motor vibrates or the disk becomes eccentric, the traverse unit 2 concomitantly rattles. Consequently, there is the danger that playback and recording of the disk are hindered.
To guarantee secure disk loading in any attitude such as horizontal installation and vertical installation and to secure a disk rotation space with a sufficient eccentric margin, JP-A-2000-311410 discloses “Disk loading unit” in which a pair of centering members are arranged on both sides of a disk conveyance path opposite each other at an interval slightly exceeding the outside diameter of an optical disk. The centering members urge the optical disk carried in on a disk tray toward the center and guide the disk into a disk drive position. In this structure, a disk damping mechanism that operates after the optical disk has been carried into the disk drive position acts to damp the optical disk onto the turntable when the disk is in the disk drive position. On the other hand, a protrusion interlocking with damping operation of the disk damping mechanism expands the interval between the pair of centering members to form an eccentric space outside the optical disk brought to the damped state.
Accordingly, in either case the unit body is placed horizontally or vertically, the pair of centering members can damp the disk while reliably centering it, thereby enabling reliable loading. Furthermore, a sufficient permissible amount can be secured for displacement of the disk damping mechanism or its optical base, the damping mechanism being mounted into the unit via a vibration-damping means such as an insulator. The insulator itself can be made of a flexible member effective in absorbing vibrations. Consequently, when the disk is rotationally driven at high speed or a disk having an eccentric center of gravity is rotated at high speed, produced vibrations can be effectively dampened or cut off.
However, the centering members and insulator are used for centering of the disk by such disk loading unit as described above and for vibration-preventing means due to eccentric center of gravity of the disk. As a result, the structure is complicated and the fabrication cost is increased, since the number of components and the number of manufacturing steps are increased,